Plasticizers are incorporated into a resin (usually a plastic or elastomer) to increase the flexibility, workability, or distensibility of the resin. The largest use of plasticizers is in the production of “plasticized” or flexible polyvinyl chloride (PVC) products. Typical uses of plasticized PVC include films, sheets, tubing, coated fabrics, wire and cable insulation and jacketing, toys, flooring materials such as vinyl sheet flooring or vinyl floor tiles, adhesives, sealants, inks, and medical products such as blood bags and tubing, and the like.
Other polymer systems that use small amounts of plasticizers include polyvinyl butyral, acrylic polymers, nylon, polyolefins, silyl-terminated polyethers, polyurethanes, and certain fluoroplastics. Plasticizers can also be used with rubber (although often these materials fall under the definition of extenders for rubber rather than plasticizers). A listing of the major plasticizers and their compatibilities with different polymer systems is provided in “Plasticizers,” A. D. Godwin, in Applied Polymer Science 21st Century, edited by C. D. Craver and C. E. Carraher, Elsevier (2000); pp. 157-175.
Commonly assigned US 2015/0140350 identified plasticized vinyl chloride formulations using methyl biphenyl carboxylic acid esters. Suitable esters are methyl biphenyl carboxylate of C4 to C14 oxo alcohols. Commonly assigned US 2014/0315021 identified various blends of commercially available plasticizers with methyl biphenyl carboxylate esters.
Methyl biphenyl carboxylate ester plasticizers having improved properties such as lower viscosity and improved gelation are desired. Such plasticizers would be useful in PVC plastisols.